The other area that Hollywood has learned how to do it right is in the use of multiple tiers of storage for recorded video. Just as in the video surveillance marketplace, video is not frequently reused or viewed after initial recording; and, just like the video surveillance market, this rapid expansion of video assets is a relatively recent change and these newer solutions are now maturing.
What existing digital storage technologies are trustworthy enough to store our video assets and ensure they will be there when we need them? Enter LTO digital computer data tape.
LTO storage has been available since 2000 and has become the de facto standard in computer data tape storage, and is heavily used in the Hollywood marketplace. The challenge for many in the video surveillance and security industry is that when they see the word “tape” their minds immediately jump to VHS. Although tape is indeed a four-letter word, if you continue reading this article holding onto that notion, you will miss out on all of its benefits.
IBM, HP and Seagate developed LTO to counter other data tape technologies, thus introducing a more open format. Much of the technology is an extension of the work done by IBM at its Tucson lab during the previous 20 years with more than 80 percent of the world’s data residing on data tape.
Around the time of the release of LTO-1, Seagate’s magnetic tape division was spun off and eventually acquired by Quantum. Today, IBM, HP, Quantum, Spectra Logic, Oracle and a number of others manufacture LTO data tape libraries, with IBM and HP manufacturing the LTO drives. The latest generation, LTO-6, began shipping in December of 2012 in 2.5-Terabyte cartridges with a retail price of about $90 per cartridge.
Adoption of LTO is already firmly established in the Hollywood media production environment. One of the driving forces behind this adoption is a mandate to many feature motion picture productions by insurance companies that content (video) captured on set or on location be archived to LTO tape on a daily basis. LTO meets the dual needs of the studios and the insurance bonding companies. The bonding companies feel more at ease because the content is archived on LTO, the same tape-based platform that banks use.
LTO is rated at up to 30 years archival shelf life. It provides for 5,000 cartridge loads/unloads and it allows for approximately 260 full file passes — with one full pass equal to writing enough data to fill an entire tape cartridge. With the sequential data structure format of video, LTO data tape becomes an ideal storage medium.
LTO for Surveillance Video
An appropriate surveillance video workflow must be put into place to properly use LTO as a video surveillance storage medium. Just as in the Hollywood market, there needs to be a way to reference the original video stored on LTO data tape without any prolonged delays. Just like Hollywood’s video editors, video surveillance operators cannot afford to wait to search and playback recorded video.
By implementing the use of low-resolution companion files, these reference files can be stored on spinning hard disk and consume a far smaller file size — thus storing a significantly longer period of time — and allow for quick and easy video playback.
As in almost every video surveillance investigation, there is a fair level of forward or backward “scrubbing” to actually find the video of interest to review. These low-resolution companion files generate very low network bandwidth use with a great side effect of loading and playing very quickly. Low-resolution companion files enable operators to bounce around recorded video looking for something specific with little overhead.
Then, just like a Hollywood editor, a surveillance video operator can select the snippet of video needed to deliver to HR/Police/Court/etc with the companion file timestamp directing the system to the specific original, untouched and unaltered video clip located on the specific LTO cartridge. This taking but a few minutes of transfer time to complete.
This best-practices approach to multi-tiered video storage also delivers appropriate “chain-of-custody” needed to submit the video as evidence in a court of law. However, it is the speed that surveillance video operators will care about most with the ability to quickly find the video they are interested in.